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Related papers: Causality constraints on radiative transfer

200 papers

Observations and magnetohydrodynamic simulations of solar and stellar atmospheres reveal an intermittent behavior or steep gradients in physical parameters, such as magnetic field, temperature, and bulk velocities. The numerical solution of…

Solar and Stellar Astrophysics · Physics 2019-03-22 Gioele Janett

We study the situation in which the distribution of temperature a body is due to its interaction with radiation. We consider the boundary value problem for the stationary radiative transfer equation under the assumption of the local…

Analysis of PDEs · Mathematics 2025-06-02 Elena Demattè , Juan J. L. Velázquez

A new method for the formal solution of the 2D radiative transfer equation in axial symmetry in the presence of arbitrary velocity fields is presented. The combination of long and short characteristics methods is used to solve the radiative…

Astrophysics · Physics 2016-08-16 D. Korčáková , J. Kubát

In this paper we show how using a relativistic kinetic equation the ensuing expression for the heat flux can be casted in the form required by Classical Irreversible Thermodynamics. Indeed, it is linearly related to the temperature and…

General Relativity and Quantum Cosmology · Physics 2009-07-31 A. Sandoval-Villalbazo , A. L. Garcia-Perciante , L. S. Garcia-Colin

It is shown that thermal fluctuations present in a simple non-degenerate relativistic fluid satisfy a wave equation in the Euler regime. The characteristic propagation speeds are calculated and the classical expression for the speed of…

General Relativity and Quantum Cosmology · Physics 2009-05-19 A. Sandoval-Villalbazo , D. Brun

Radiative transfer and radiation hydrodynamics use the relativistic Boltzmann equation to describe the kinetics of photons. It is difficult to solve the six-dimensional time-dependent transfer equation unless the problem is highly symmetric…

Instrumentation and Methods for Astrophysics · Physics 2011-02-09 Chi-kwan Chan

Heterogeneity can be accounted for by a random potential in the wave equation. For acoustic waves in a fluid with fluctuations of both density and compressibility (as well as for electromagnetic waves in a medium with fluctuation of both…

Classical Physics · Physics 2016-12-07 Ibrahim Baydoun , Diego Baresch , Romain Pierrat , Arnaud Derode

This paper focuses on the nonlinear Milne problem of the radiative heat transfer system on the half-space. The nonlinear model is described by a second order ODE for temperature coupled to transport equation for radiative intensity. The…

Analysis of PDEs · Mathematics 2022-07-25 Mohamed Ghattassi , Xiaokai Huo , Nader Masmoudi

The problem of linear instability of a nonlinear traveling wave in a canonical Hamiltonian system with translational symmetry subject to superharmonic perturbations is discussed. It is shown that exchange of stability occurs when energy is…

Fluid Dynamics · Physics 2019-08-09 N. Sato , M. Yamada

A system of drift-diffusion equations with electric field under Dirichlet boundary conditions is analyzed. The system of strongly coupled parabolic equations for particle density and spin density vector describes the spin-polarized…

Analysis of PDEs · Mathematics 2014-02-26 Nicola Zamponi

We deduce the equations that describe how polarized radiation is Comptonized by a hot electron gas. Low frequencies are considered, and the equations are expanded to second order in electron velocities. Induced scattering terms are included…

Astrophysics · Physics 2009-10-31 Frode K. Hansen , Per B. Lilje

The lack of formulation of macroscopic equations for irreversible dynamics of viscous heat-conducting media compatible with the causality principle of Einstein's Special Relativity and the Euler-Lagrange structure of General Relativity is a…

General Relativity and Quantum Cosmology · Physics 2020-03-31 Evgeniy Romenski , Ilya Peshkov , Michael Dumbser , and Francesco Fambri

This work presents efficient solution techniques for radiative transfer in the smoothed particle hydrodynamics discretization. Two choices that impact efficiency are how the material and radiation energy are coupled, which determines the…

Computational Physics · Physics 2021-03-17 Brody R. Bassett , J. Michael Owen , Thomas A. Brunner

In the standard form of the relativistic heat equation used in astrophysics, information propagates instantaneously, rather than being limited by the speed of light as demanded by relativity. We show how this equation nonetheless follows…

High Energy Astrophysical Phenomena · Physics 2018-07-13 S. K. Lander , N. Andersson

A Coefficient Inverse Problem for the radiative transport equation is considered. The globally convergent numerical method, the so-called convexification, is developed. For the first time, the viscosity solution is considered for a boundary…

Numerical Analysis · Mathematics 2023-03-17 Michael V. Klibanov , Jingzhi Li , Zhipeng Yang

The stability conditions of a relativistic hydrodynamic theory can be derived directly from the requirement that the entropy should be maximised in equilibrium. Here we use a simple geometrical argument to prove that, if the hydrodynamic…

General Relativity and Quantum Cosmology · Physics 2022-01-11 Lorenzo Gavassino , Marco Antonelli , Brynmor Haskell

This paper addresses the existence and spectral stability of traveling fronts for nonlinear hyperbolic equations with a positive "damping" term and a reaction function of bistable type. Particular cases of the former include the relaxed…

Analysis of PDEs · Mathematics 2018-02-27 Corrado Lattanzio , Corrado Mascia , Ramón G. Plaza , Chiara Simeoni

This paper concerns the derivation of radiative transfer equations for acoustic waves propagating in a randomly fluctuating half-space in the weak-scattering regime, and the study of boundary effects through an asymptotic analysis of the…

Classical Physics · Physics 2022-12-01 Adel Messaoudi , Regis Cottereau , Christophe Gomez

When the steady states at infinity become unstable through a pattern forming bifurcation, a travelling wave may bifurcate into a modulated front which is time-periodic in a moving frame. This scenario has been studied by B.Sandstede and…

Analysis of PDEs · Mathematics 2007-05-23 Thierry Gallay , Guido Schneider , Hannes Uecker

We investigate heat propagation in rigidly rotating bodies within the theory of general relativity. Using a first-order gradient expansion, we derive a universal partial differential equation governing the temperature evolution. This…

General Relativity and Quantum Cosmology · Physics 2025-11-21 Lorenzo Gavassino , Marco Antonelli